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[+44 330 383 8000](tel:+443303838000 "+44 330 383 8000") ![](/images/getstarted-writetous-navbar-int_ZY7MOf.webp) ### Write to us Fill out our request form. Our experts will respond as soon as possible. [Write to us](/gb/request-information "Write to us") ### uaCSTA connection [What is CTI?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/uacsta-connection#section-3) [CTI and CSTA: How can uaCSTA aid your business?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/uacsta-connection#section-4) # uaCSTA connection **What is uaCSTA?** UaCSTA is the abbreviation for **User Agent Computer Supported Telecommunications Applications,** and is a standard that enables Computer Technology Integration (CTI). The Computer Supported Telecommunications Applications (CSTA) protocol serves as the interface for smart connections between computer programs and telephone systems. Using a CSTA server, the user can access and control an integrated phone from a CTI application installed on a personal computer (PC) or a laptop. The CSTA interface provides services such as answering, transferring, holding, and retrieving calls. It allows dedicated control and monitoring for all phone lines that are connected to the computer. The CSTA protocol defines the data to be transmitted and the messages to be exchanged between the telephone system and the computer. It can operate serially via digital ISDN (Integrated Services Digital Network) or the data can be transferred via [Transmission Control Protocol/Internet Protocol (TCP/IP)](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/tcp-ip). ### What is CTI? **Computer Telephony Integration (CTI)** is a technology that enables synchronised integration between a laptop or personal computer and a telephone. It allows computer software such as email applications to connect the user directly to the telephone system, with call functions just a click away, and to control the phone from his computer. NFON’s CTI solutions that provide this type of integration include [NCTI](t3://page?uid=1300) Standard, NCTI Premium and NCTI Pro. ### CTI and CSTA: How can uaCSTA aid your business? If a user’s computer as well as the phone system is running uaCSTA-compatible software, they will be able to exchange information with each other, allowing them to perform the functions required for Computer Telephony Integration (CTI). Some email applications include features that work with CTI – for example, features enabling users to make phone calls directly from their emails, or to save notes related to the contact or conversation for future reference. CSTA interface transmissions allow CTI compatible solutions without increasing the complexity of the software, while also helping to avoid performance bottlenecks, code size problems or any other overheads. NFON’s CTI solution, NCTI, is designed to sit on top of cloud telephone system, [Cloudya](t3://page?uid=16). It complements Cloudya’s many communication and collaboration features – one number, one inbox, meet & share and more – with deep business process integration. This gives organisations complete freedom in choosing their preferred communication devices and environments. NCTI is available in three different options, Standard, Premium and Pro, to cover various integration needs. From data-read integration that gives call centre employees a full view of all relevant customer information to deep process integration with Customer Relationship Management (CRM) solutions and Unified Communications (UC) features such as interactive chats and video calls, NCTI made by NFON is flexible enough to adapt to every organisation’s needs. The combination of Cloudya and NCTI helps businesses maximise productivity and efficiency, and facilitates seamless communication from anywhere. It creates a communication process that is independent of expensive tools and free of geographical limitations – all in one single, user-friendly interface. No overcomplicated processes, just simplicity. Simply plug in one device and all your connected devices are only a click away. ### NCTI ![](https://a.storyblok.com/f/290788/660572c74b/ncti_uacsta.png) ### Related Articles ### Computer Telephony Integration (CTI) CTI is the abbreviation for the technical term Computer Telephony Integration. It refers to a communications solution that, with the assistance of computer software, allows functions of the phone system to be used in conjunction with information stored in the computer system, such as phone numbers. CTI enables control of the phone through the PC. This allows computer software such as email programs to connect you to the telephone system with just the click of a mouse. With incoming calls, a corresponding CTI function can display information about the caller from a [CRM system](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/customer-relationship-management), such as their contact details or call history. These additional functions make communication in business more efficient and allow for the better exchange of information. To operate Computer Telephony Integration, the computer needs the appropriate software to control the system phone or communicate with the [telephone system](t3://page?uid=16). Many PBX manufacturers offer such software solutions for their devices. To facilitate the connection of CRM or back-end systems with as little effort as possible, the CTI programs usually have software modules that can communicate with popular CRM and back-end systems via standardised interfaces. For communication between the telephone system and the computer software, there are standardised protocols such as [CSTA](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/csta) (Computer Supported Telecommunications Applications). This protocol defines the type and format of the data to be transmitted without specifying the actual transport layer, thereby allowing CTI solutions to be implemented by many more manufacturers. Want to know more? [Check our leaflets](https://www.nfon.com/en/service/documentation/manuals/software)! [Computer Telephony Integration (CTI)](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/cti) ### TCP/IP The acronym TCP/IP stands for Transmission Control Protocol/Internet Protocol and refers to a family of network protocols which are the basis for communication and data exchange over the internet as well as on private IP networks. The development of TCP/IP already began in the 1970s and traces back to the work of DARPA. Whilst the protocol family used to compete with alternative protocols such as AppleTalk by Apple, IPX/SPX by Novell or NetBEUI by Microsoft, TCP/IP has now established itself as a universal and worldwide popular protocol. It is platform-independent and available for devices with all operating systems imaginable. The reasons for the success of the protocol family are the victory of the Internet as well as its flexibility and versatility. 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